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@@ -1,4 +1,4 @@
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<img src="./denoising-diffusion.png" width="500px"></img>
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<img src="./images/denoising-diffusion.png" width="500px"></img>
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## Denoising Diffusion Probabilistic Model, in Pytorch
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@@ -10,7 +10,9 @@ Youtube AI Educators - <a href="https://www.youtube.com/watch?v=W-O7AZNzbzQ">Yan
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<a href="https://huggingface.co/blog/annotated-diffusion">Annotated code</a> by Research Scientists / Engineers from <a href="https://huggingface.co/">🤗 Huggingface</a>
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<img src="./sample.png" width="500px"><img>
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Update: Turns out none of the technicalities really matters at all | <a href="https://arxiv.org/abs/2208.09392">"Cold Diffusion" paper</a>
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<img src="./images/sample.png" width="500px"><img>
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[](https://badge.fury.io/py/denoising-diffusion-pytorch)
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@@ -69,7 +71,7 @@ trainer = Trainer(
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diffusion,
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'path/to/your/images',
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train_batch_size = 32,
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train_lr = 1e-4,
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train_lr = 8e-5,
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train_num_steps = 700000, # total training steps
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gradient_accumulate_every = 2, # gradient accumulation steps
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ema_decay = 0.995, # exponential moving average decay
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@@ -170,3 +172,24 @@ $ accelerate launch train.py
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volume = {abs/2010.02502}
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}
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```
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```bibtex
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@misc{chen2022analog,
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title = {Analog Bits: Generating Discrete Data using Diffusion Models with Self-Conditioning},
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author = {Ting Chen and Ruixiang Zhang and Geoffrey Hinton},
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year = {2022},
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eprint = {2208.04202},
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archivePrefix = {arXiv},
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primaryClass = {cs.CV}
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}
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```
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```bibtex
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@article{Qiao2019WeightS,
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title = {Weight Standardization},
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author = {Siyuan Qiao and Huiyu Wang and Chenxi Liu and Wei Shen and Alan Loddon Yuille},
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journal = {ArXiv},
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year = {2019},
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volume = {abs/1903.10520}
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}
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```
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@@ -127,6 +127,7 @@ class ContinuousTimeGaussianDiffusion(nn.Module):
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):
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super().__init__()
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assert model.learned_sinusoidal_cond
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assert not model.self_condition, 'not supported yet'
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self.model = model
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@@ -1,23 +1,23 @@
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import math
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import copy
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from pathlib import Path
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from random import random
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from functools import partial
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from collections import namedtuple
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from multiprocessing import cpu_count
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import torch
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from torch import nn, einsum
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import torch.nn.functional as F
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from inspect import isfunction
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from collections import namedtuple
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from functools import partial
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from torch.utils.data import Dataset, DataLoader
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from multiprocessing import cpu_count
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from pathlib import Path
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from torch.optim import Adam
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from torchvision import transforms as T, utils
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from PIL import Image
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from einops import rearrange, reduce
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from einops.layers.torch import Rearrange
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from PIL import Image
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from tqdm.auto import tqdm
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from ema_pytorch import EMA
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@@ -35,7 +35,10 @@ def exists(x):
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def default(val, d):
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if exists(val):
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return val
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return d() if isfunction(d) else d
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return d() if callable(d) else d
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def identity(t, *args, **kwargs):
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return t
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def cycle(dl):
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while True:
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@@ -58,6 +61,9 @@ def convert_image_to(img_type, image):
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return image.convert(img_type)
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return image
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def l2norm(t):
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return F.normalize(t, dim = -1)
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# normalization functions
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def normalize_to_neg_one_to_one(img):
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@@ -85,17 +91,31 @@ def Upsample(dim, dim_out = None):
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def Downsample(dim, dim_out = None):
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return nn.Conv2d(dim, default(dim_out, dim), 4, 2, 1)
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class WeightStandardizedConv2d(nn.Conv2d):
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"""
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https://arxiv.org/abs/1903.10520
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weight standardization purportedly works synergistically with group normalization
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"""
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def forward(self, x):
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eps = 1e-5 if x.dtype == torch.float32 else 1e-3
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weight = self.weight
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mean = reduce(weight, 'o ... -> o 1 1 1', 'mean')
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var = reduce(weight, 'o ... -> o 1 1 1', partial(torch.var, unbiased = False))
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normalized_weight = (weight - mean) * (var + eps).rsqrt()
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return F.conv2d(x, normalized_weight, self.bias, self.stride, self.padding, self.dilation, self.groups)
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class LayerNorm(nn.Module):
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def __init__(self, dim, eps = 1e-5):
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def __init__(self, dim):
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super().__init__()
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self.eps = eps
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self.g = nn.Parameter(torch.ones(1, dim, 1, 1))
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self.b = nn.Parameter(torch.zeros(1, dim, 1, 1))
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def forward(self, x):
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eps = 1e-5 if x.dtype == torch.float32 else 1e-3
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var = torch.var(x, dim = 1, unbiased = False, keepdim = True)
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mean = torch.mean(x, dim = 1, keepdim = True)
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return (x - mean) / (var + self.eps).sqrt() * self.g + self.b
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return (x - mean) * (var + eps).rsqrt() * self.g
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class PreNorm(nn.Module):
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def __init__(self, dim, fn):
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@@ -145,7 +165,7 @@ class LearnedSinusoidalPosEmb(nn.Module):
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class Block(nn.Module):
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def __init__(self, dim, dim_out, groups = 8):
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super().__init__()
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self.proj = nn.Conv2d(dim, dim_out, 3, padding = 1)
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self.proj = WeightStandardizedConv2d(dim, dim_out, 3, padding = 1)
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self.norm = nn.GroupNorm(groups, dim_out)
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self.act = nn.SiLU()
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@@ -208,6 +228,8 @@ class LinearAttention(nn.Module):
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k = k.softmax(dim = -1)
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q = q * self.scale
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v = v / (h * w)
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context = torch.einsum('b h d n, b h e n -> b h d e', k, v)
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out = torch.einsum('b h d e, b h d n -> b h e n', context, q)
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@@ -215,9 +237,9 @@ class LinearAttention(nn.Module):
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return self.to_out(out)
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class Attention(nn.Module):
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def __init__(self, dim, heads = 4, dim_head = 32):
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def __init__(self, dim, heads = 4, dim_head = 32, scale = 10):
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super().__init__()
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self.scale = dim_head ** -0.5
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self.scale = scale
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self.heads = heads
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hidden_dim = dim_head * heads
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self.to_qkv = nn.Conv2d(dim, hidden_dim * 3, 1, bias = False)
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@@ -227,12 +249,11 @@ class Attention(nn.Module):
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b, c, h, w = x.shape
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qkv = self.to_qkv(x).chunk(3, dim = 1)
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q, k, v = map(lambda t: rearrange(t, 'b (h c) x y -> b h c (x y)', h = self.heads), qkv)
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q = q * self.scale
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sim = einsum('b h d i, b h d j -> b h i j', q, k)
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sim = sim - sim.amax(dim = -1, keepdim = True).detach()
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q, k = map(l2norm, (q, k))
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sim = einsum('b h d i, b h d j -> b h i j', q, k) * self.scale
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attn = sim.softmax(dim = -1)
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out = einsum('b h i j, b h d j -> b h i d', attn, v)
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out = rearrange(out, 'b h (x y) d -> b (h d) x y', x = h, y = w)
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return self.to_out(out)
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@@ -247,6 +268,7 @@ class Unet(nn.Module):
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out_dim = None,
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dim_mults=(1, 2, 4, 8),
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channels = 3,
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self_condition = False,
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resnet_block_groups = 8,
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learned_variance = False,
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learned_sinusoidal_cond = False,
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@@ -257,9 +279,11 @@ class Unet(nn.Module):
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# determine dimensions
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self.channels = channels
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self.self_condition = self_condition
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input_channels = channels * (2 if self_condition else 1)
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init_dim = default(init_dim, dim)
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self.init_conv = nn.Conv2d(channels, init_dim, 7, padding = 3)
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self.init_conv = nn.Conv2d(input_channels, init_dim, 7, padding = 3)
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dims = [init_dim, *map(lambda m: dim * m, dim_mults)]
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in_out = list(zip(dims[:-1], dims[1:]))
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@@ -323,7 +347,11 @@ class Unet(nn.Module):
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self.final_res_block = block_klass(dim * 2, dim, time_emb_dim = time_dim)
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self.final_conv = nn.Conv2d(dim, self.out_dim, 1)
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def forward(self, x, time):
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def forward(self, x, time, x_self_cond = None):
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if self.self_condition:
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x_self_cond = default(x_self_cond, lambda: torch.zeros_like(x))
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x = torch.cat((x_self_cond, x), dim = 1)
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x = self.init_conv(x)
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r = x.clone()
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@@ -391,7 +419,6 @@ class GaussianDiffusion(nn.Module):
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model,
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*,
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image_size,
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channels = 3,
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timesteps = 1000,
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sampling_timesteps = None,
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loss_type = 'l1',
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@@ -403,10 +430,14 @@ class GaussianDiffusion(nn.Module):
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):
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super().__init__()
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assert not (type(self) == GaussianDiffusion and model.channels != model.out_dim)
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assert not model.learned_sinusoidal_cond
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self.channels = channels
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self.image_size = image_size
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self.model = model
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self.channels = self.model.channels
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self.self_condition = self.model.self_condition
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self.image_size = image_size
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self.objective = objective
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assert objective in {'pred_noise', 'pred_x0'}, 'objective must be either pred_noise (predict noise) or pred_x0 (predict image start)'
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@@ -476,7 +507,7 @@ class GaussianDiffusion(nn.Module):
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def predict_noise_from_start(self, x_t, t, x0):
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return (
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(x0 - extract(self.sqrt_recip_alphas_cumprod, t, x_t.shape) * x_t) / \
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(extract(self.sqrt_recip_alphas_cumprod, t, x_t.shape) * x_t - x0) / \
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extract(self.sqrt_recipm1_alphas_cumprod, t, x_t.shape)
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)
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@@ -489,36 +520,40 @@ class GaussianDiffusion(nn.Module):
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posterior_log_variance_clipped = extract(self.posterior_log_variance_clipped, t, x_t.shape)
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return posterior_mean, posterior_variance, posterior_log_variance_clipped
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def model_predictions(self, x, t):
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model_output = self.model(x, t)
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def model_predictions(self, x, t, x_self_cond = None, clip_x_start = False):
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model_output = self.model(x, t, x_self_cond)
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maybe_clip = partial(torch.clamp, min = -1., max = 1.) if clip_x_start else identity
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if self.objective == 'pred_noise':
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pred_noise = model_output
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x_start = self.predict_start_from_noise(x, t, model_output)
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x_start = self.predict_start_from_noise(x, t, pred_noise)
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x_start = maybe_clip(x_start)
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elif self.objective == 'pred_x0':
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pred_noise = self.predict_noise_from_start(x, t, model_output)
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x_start = model_output
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x_start = maybe_clip(x_start)
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pred_noise = self.predict_noise_from_start(x, t, x_start)
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return ModelPrediction(pred_noise, x_start)
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def p_mean_variance(self, x, t, clip_denoised: bool):
|
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preds = self.model_predictions(x, t)
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def p_mean_variance(self, x, t, x_self_cond = None, clip_denoised = True):
|
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preds = self.model_predictions(x, t, x_self_cond)
|
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x_start = preds.pred_x_start
|
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|
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if clip_denoised:
|
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x_start.clamp_(-1., 1.)
|
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|
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model_mean, posterior_variance, posterior_log_variance = self.q_posterior(x_start = x_start, x_t = x, t = t)
|
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return model_mean, posterior_variance, posterior_log_variance
|
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return model_mean, posterior_variance, posterior_log_variance, x_start
|
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|
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@torch.no_grad()
|
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def p_sample(self, x, t: int, clip_denoised = True):
|
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def p_sample(self, x, t: int, x_self_cond = None, clip_denoised = True):
|
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b, *_, device = *x.shape, x.device
|
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batched_times = torch.full((x.shape[0],), t, device = x.device, dtype = torch.long)
|
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model_mean, _, model_log_variance = self.p_mean_variance(x = x, t = batched_times, clip_denoised = clip_denoised)
|
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model_mean, _, model_log_variance, x_start = self.p_mean_variance(x = x, t = batched_times, x_self_cond = x_self_cond, clip_denoised = clip_denoised)
|
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noise = torch.randn_like(x) if t > 0 else 0. # no noise if t == 0
|
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return model_mean + (0.5 * model_log_variance).exp() * noise
|
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pred_img = model_mean + (0.5 * model_log_variance).exp() * noise
|
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return pred_img, x_start
|
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|
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@torch.no_grad()
|
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def p_sample_loop(self, shape):
|
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@@ -526,8 +561,11 @@ class GaussianDiffusion(nn.Module):
|
||||
|
||||
img = torch.randn(shape, device=device)
|
||||
|
||||
for t in tqdm(reversed(range(0, self.num_timesteps)), desc = 'sampling loop time step'):
|
||||
img = self.p_sample(img, t)
|
||||
x_start = None
|
||||
|
||||
for t in tqdm(reversed(range(0, self.num_timesteps)), desc = 'sampling loop time step', total = self.num_timesteps):
|
||||
self_cond = x_start if self.self_condition else None
|
||||
img, x_start = self.p_sample(img, t, self_cond)
|
||||
|
||||
img = unnormalize_to_zero_to_one(img)
|
||||
return img
|
||||
@@ -536,30 +574,34 @@ class GaussianDiffusion(nn.Module):
|
||||
def ddim_sample(self, shape, clip_denoised = True):
|
||||
batch, device, total_timesteps, sampling_timesteps, eta, objective = shape[0], self.betas.device, self.num_timesteps, self.sampling_timesteps, self.ddim_sampling_eta, self.objective
|
||||
|
||||
times = torch.linspace(0., total_timesteps, steps = sampling_timesteps + 2)[:-1]
|
||||
|
||||
times = torch.linspace(-1, total_timesteps - 1, steps=sampling_timesteps + 1) # [-1, 0, 1, 2, ..., T-1] when sampling_timesteps == total_timesteps
|
||||
times = list(reversed(times.int().tolist()))
|
||||
time_pairs = list(zip(times[:-1], times[1:]))
|
||||
time_pairs = list(zip(times[:-1], times[1:])) # [(T-1, T-2), (T-2, T-3), ..., (1, 0), (0, -1)]
|
||||
|
||||
img = torch.randn(shape, device = device)
|
||||
|
||||
x_start = None
|
||||
|
||||
for time, time_next in tqdm(time_pairs, desc = 'sampling loop time step'):
|
||||
alpha = self.alphas_cumprod_prev[time]
|
||||
alpha_next = self.alphas_cumprod_prev[time_next]
|
||||
time_cond = torch.full((batch,), time, device=device, dtype=torch.long)
|
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self_cond = x_start if self.self_condition else None
|
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pred_noise, x_start, *_ = self.model_predictions(img, time_cond, self_cond, clip_x_start = clip_denoised)
|
||||
|
||||
time_cond = torch.full((batch,), time, device = device, dtype = torch.long)
|
||||
if time_next < 0:
|
||||
img = x_start
|
||||
continue
|
||||
|
||||
pred_noise, x_start, *_ = self.model_predictions(img, time_cond)
|
||||
alpha = self.alphas_cumprod[time]
|
||||
alpha_next = self.alphas_cumprod[time_next]
|
||||
|
||||
if clip_denoised:
|
||||
x_start.clamp_(-1., 1.)
|
||||
sigma = eta * ((1 - alpha / alpha_next) * (1 - alpha_next) / (1 - alpha)).sqrt()
|
||||
c = (1 - alpha_next - sigma ** 2).sqrt()
|
||||
|
||||
c1 = eta * ((1 - alpha / alpha_next) * (1 - alpha_next) / (1 - alpha)).sqrt()
|
||||
c2 = ((1 - alpha_next) - torch.square(c1)).sqrt()
|
||||
noise = torch.randn_like(img)
|
||||
|
||||
img = x_start * alpha_next.sqrt() + \
|
||||
c1 * torch.randn_like(img) + \
|
||||
c2 * pred_noise
|
||||
c * pred_noise + \
|
||||
sigma * noise
|
||||
|
||||
img = unnormalize_to_zero_to_one(img)
|
||||
return img
|
||||
@@ -577,11 +619,11 @@ class GaussianDiffusion(nn.Module):
|
||||
|
||||
assert x1.shape == x2.shape
|
||||
|
||||
t_batched = torch.stack([torch.tensor(t, device=device)] * b)
|
||||
xt1, xt2 = map(lambda x: self.q_sample(x, t=t_batched), (x1, x2))
|
||||
t_batched = torch.stack([torch.tensor(t, device = device)] * b)
|
||||
xt1, xt2 = map(lambda x: self.q_sample(x, t = t_batched), (x1, x2))
|
||||
|
||||
img = (1 - lam) * xt1 + lam * xt2
|
||||
for i in tqdm(reversed(range(0, t)), desc='interpolation sample time step', total=t):
|
||||
for i in tqdm(reversed(range(0, t)), desc = 'interpolation sample time step', total = t):
|
||||
img = self.p_sample(img, torch.full((b,), i, device=device, dtype=torch.long))
|
||||
|
||||
return img
|
||||
@@ -607,8 +649,23 @@ class GaussianDiffusion(nn.Module):
|
||||
b, c, h, w = x_start.shape
|
||||
noise = default(noise, lambda: torch.randn_like(x_start))
|
||||
|
||||
# noise sample
|
||||
|
||||
x = self.q_sample(x_start = x_start, t = t, noise = noise)
|
||||
model_out = self.model(x, t)
|
||||
|
||||
# if doing self-conditioning, 50% of the time, predict x_start from current set of times
|
||||
# and condition with unet with that
|
||||
# this technique will slow down training by 25%, but seems to lower FID significantly
|
||||
|
||||
x_self_cond = None
|
||||
if self.self_condition and random() < 0.5:
|
||||
with torch.no_grad():
|
||||
x_self_cond = self.model_predictions(x, t).pred_x_start
|
||||
x_self_cond.detach_()
|
||||
|
||||
# predict and take gradient step
|
||||
|
||||
model_out = self.model(x, t, x_self_cond)
|
||||
|
||||
if self.objective == 'pred_noise':
|
||||
target = noise
|
||||
@@ -680,6 +737,7 @@ class Trainer(object):
|
||||
train_num_steps = 100000,
|
||||
ema_update_every = 10,
|
||||
ema_decay = 0.995,
|
||||
adam_betas = (0.9, 0.99),
|
||||
save_and_sample_every = 1000,
|
||||
num_samples = 25,
|
||||
results_folder = './results',
|
||||
@@ -714,11 +772,12 @@ class Trainer(object):
|
||||
self.ds = Dataset(folder, self.image_size, augment_horizontal_flip = augment_horizontal_flip, convert_image_to = convert_image_to)
|
||||
dl = DataLoader(self.ds, batch_size = train_batch_size, shuffle = True, pin_memory = True, num_workers = cpu_count())
|
||||
|
||||
dl = self.accelerator.prepare(dl)
|
||||
self.dl = cycle(dl)
|
||||
|
||||
# optimizer
|
||||
|
||||
self.opt = Adam(diffusion_model.parameters(), lr = train_lr)
|
||||
self.opt = Adam(diffusion_model.parameters(), lr = train_lr, betas = adam_betas)
|
||||
|
||||
# for logging results in a folder periodically
|
||||
|
||||
@@ -734,7 +793,7 @@ class Trainer(object):
|
||||
|
||||
# prepare model, dataloader, optimizer with accelerator
|
||||
|
||||
self.model, self.dl, self.opt = self.accelerator.prepare(self.model, self.dl, self.opt)
|
||||
self.model, self.opt = self.accelerator.prepare(self.model, self.opt)
|
||||
|
||||
def save(self, milestone):
|
||||
if not self.accelerator.is_local_main_process:
|
||||
@@ -751,7 +810,10 @@ class Trainer(object):
|
||||
torch.save(data, str(self.results_folder / f'model-{milestone}.pt'))
|
||||
|
||||
def load(self, milestone):
|
||||
data = torch.load(str(self.results_folder / f'model-{milestone}.pt'))
|
||||
accelerator = self.accelerator
|
||||
device = accelerator.device
|
||||
|
||||
data = torch.load(str(self.results_folder / f'model-{milestone}.pt'), map_location=device)
|
||||
|
||||
model = self.accelerator.unwrap_model(self.model)
|
||||
model.load_state_dict(data['model'])
|
||||
@@ -771,14 +833,19 @@ class Trainer(object):
|
||||
|
||||
while self.step < self.train_num_steps:
|
||||
|
||||
total_loss = 0.
|
||||
|
||||
for _ in range(self.gradient_accumulate_every):
|
||||
data = next(self.dl).to(device)
|
||||
|
||||
with self.accelerator.autocast():
|
||||
loss = self.model(data)
|
||||
self.accelerator.backward(loss / self.gradient_accumulate_every)
|
||||
loss = loss / self.gradient_accumulate_every
|
||||
total_loss += loss.item()
|
||||
|
||||
pbar.set_description(f'loss: {loss.item():.4f}')
|
||||
self.accelerator.backward(loss)
|
||||
|
||||
pbar.set_description(f'loss: {total_loss:.4f}')
|
||||
|
||||
accelerator.wait_for_everyone()
|
||||
|
||||
@@ -787,6 +854,7 @@ class Trainer(object):
|
||||
|
||||
accelerator.wait_for_everyone()
|
||||
|
||||
self.step += 1
|
||||
if accelerator.is_main_process:
|
||||
self.ema.to(device)
|
||||
self.ema.update()
|
||||
@@ -803,7 +871,6 @@ class Trainer(object):
|
||||
utils.save_image(all_images, str(self.results_folder / f'sample-{milestone}.png'), nrow = int(math.sqrt(self.num_samples)))
|
||||
self.save(milestone)
|
||||
|
||||
self.step += 1
|
||||
pbar.update(1)
|
||||
|
||||
accelerator.print('training complete')
|
||||
|
||||
@@ -1,4 +1,5 @@
|
||||
from math import sqrt
|
||||
from random import random
|
||||
import torch
|
||||
from torch import nn, einsum
|
||||
import torch.nn.functional as F
|
||||
@@ -52,6 +53,7 @@ class ElucidatedDiffusion(nn.Module):
|
||||
):
|
||||
super().__init__()
|
||||
assert net.learned_sinusoidal_cond
|
||||
self.self_condition = net.self_condition
|
||||
|
||||
self.net = net
|
||||
|
||||
@@ -99,7 +101,7 @@ class ElucidatedDiffusion(nn.Module):
|
||||
# preconditioned network output
|
||||
# equation (7) in the paper
|
||||
|
||||
def preconditioned_network_forward(self, noised_images, sigma, clamp = False):
|
||||
def preconditioned_network_forward(self, noised_images, sigma, self_cond = None, clamp = False):
|
||||
batch, device = noised_images.shape[0], noised_images.device
|
||||
|
||||
if isinstance(sigma, float):
|
||||
@@ -109,7 +111,8 @@ class ElucidatedDiffusion(nn.Module):
|
||||
|
||||
net_out = self.net(
|
||||
self.c_in(padded_sigma) * noised_images,
|
||||
self.c_noise(sigma)
|
||||
self.c_noise(sigma),
|
||||
self_cond
|
||||
)
|
||||
|
||||
out = self.c_skip(padded_sigma) * noised_images + self.c_out(padded_sigma) * net_out
|
||||
@@ -160,6 +163,10 @@ class ElucidatedDiffusion(nn.Module):
|
||||
|
||||
images = init_sigma * torch.randn(shape, device = self.device)
|
||||
|
||||
# for self conditioning
|
||||
|
||||
x_start = None
|
||||
|
||||
# gradually denoise
|
||||
|
||||
for sigma, sigma_next, gamma in tqdm(sigmas_and_gammas, desc = 'sampling time step'):
|
||||
@@ -170,7 +177,9 @@ class ElucidatedDiffusion(nn.Module):
|
||||
sigma_hat = sigma + gamma * sigma
|
||||
images_hat = images + sqrt(sigma_hat ** 2 - sigma ** 2) * eps
|
||||
|
||||
model_output = self.preconditioned_network_forward(images_hat, sigma_hat, clamp = clamp)
|
||||
self_cond = x_start if self.self_condition else None
|
||||
|
||||
model_output = self.preconditioned_network_forward(images_hat, sigma_hat, self_cond, clamp = clamp)
|
||||
denoised_over_sigma = (images_hat - model_output) / sigma_hat
|
||||
|
||||
images_next = images_hat + (sigma_next - sigma_hat) * denoised_over_sigma
|
||||
@@ -178,11 +187,14 @@ class ElucidatedDiffusion(nn.Module):
|
||||
# second order correction, if not the last timestep
|
||||
|
||||
if sigma_next != 0:
|
||||
model_output_next = self.preconditioned_network_forward(images_next, sigma_next, clamp = clamp)
|
||||
self_cond = model_output if self.self_condition else None
|
||||
|
||||
model_output_next = self.preconditioned_network_forward(images_next, sigma_next, self_cond, clamp = clamp)
|
||||
denoised_prime_over_sigma = (images_next - model_output_next) / sigma_next
|
||||
images_next = images_hat + 0.5 * (sigma_next - sigma_hat) * (denoised_over_sigma + denoised_prime_over_sigma)
|
||||
|
||||
images = images_next
|
||||
x_start = model_output
|
||||
|
||||
images = images.clamp(-1., 1.)
|
||||
return unnormalize_to_zero_to_one(images)
|
||||
@@ -210,7 +222,15 @@ class ElucidatedDiffusion(nn.Module):
|
||||
|
||||
noised_images = images + padded_sigmas * noise # alphas are 1. in the paper
|
||||
|
||||
denoised = self.preconditioned_network_forward(noised_images, sigmas)
|
||||
self_cond = None
|
||||
|
||||
if self.self_condition and random() < 0.5:
|
||||
# from hinton's group's bit diffusion paper
|
||||
with torch.no_grad():
|
||||
self_cond = self.preconditioned_network_forward(noised_images, sigmas)
|
||||
self_cond.detach_()
|
||||
|
||||
denoised = self.preconditioned_network_forward(noised_images, sigmas, self_cond)
|
||||
|
||||
losses = F.mse_loss(denoised, images, reduction = 'none')
|
||||
losses = reduce(losses, 'b ... -> b', 'mean')
|
||||
|
||||
@@ -77,6 +77,8 @@ class LearnedGaussianDiffusion(GaussianDiffusion):
|
||||
):
|
||||
super().__init__(model, *args, **kwargs)
|
||||
assert model.out_dim == (model.channels * 2), 'dimension out of unet must be twice the number of channels for learned variance - you can also set the `learned_variance` keyword argument on the Unet to be `True`'
|
||||
assert not model.self_condition, 'not supported yet'
|
||||
|
||||
self.vb_loss_weight = vb_loss_weight
|
||||
|
||||
def model_predictions(self, x, t):
|
||||
|
||||
@@ -31,6 +31,7 @@ class WeightedObjectiveGaussianDiffusion(GaussianDiffusion):
|
||||
super().__init__(model, *args, **kwargs)
|
||||
channels = model.channels
|
||||
assert model.out_dim == (channels * 2 + 2), 'dimension out (out_dim) of unet must be twice the number of channels + 2 (for the softmax weighted sum) - for channels of 3, this should be (3 * 2) + 2 = 8'
|
||||
assert not model.self_condition, 'not supported yet'
|
||||
assert not self.is_ddim_sampling, 'ddim sampling cannot be used'
|
||||
|
||||
self.split_dims = (channels, channels, 2)
|
||||
|
||||
|
Before Width: | Height: | Size: 40 KiB After Width: | Height: | Size: 40 KiB |
|
Before Width: | Height: | Size: 842 KiB After Width: | Height: | Size: 842 KiB |
@@ -3,7 +3,7 @@ from setuptools import setup, find_packages
|
||||
setup(
|
||||
name = 'denoising-diffusion-pytorch',
|
||||
packages = find_packages(),
|
||||
version = '0.25.1',
|
||||
version = '0.27.9',
|
||||
license='MIT',
|
||||
description = 'Denoising Diffusion Probabilistic Models - Pytorch',
|
||||
author = 'Phil Wang',
|
||||
@@ -30,4 +30,4 @@ setup(
|
||||
'License :: OSI Approved :: MIT License',
|
||||
'Programming Language :: Python :: 3.6',
|
||||
],
|
||||
)
|
||||
)
|
||||
|
||||
Reference in New Issue
Block a user